Liquefied petroleum gas (LPG) is used with gasoline for car fuel since it has a high octane number, a superior thermal resistance, and inexpensive prices.
The LPG supplied to a car engine is in a liquid form. When the LPG in liquid form is vaporized, the fuel and air can be easily mixed so that combustibility can increase. In other words, LPG prevents frequent knocking and eliminates phenomena such as vapor-lock and percolation, in comparison with gasoline or light oil used for a conventional car engine. Therefore, the application range of LPG has increased as an alternative fuel of gasoline or diesel.
A device of supplying the LPG supplies LPG in the liquid form to a gas injector by using a fuel pump, the LPG is sprayed through the gas injector to a cylinder, and the sprayed LPG is mixed with air to be vaporized.
A dual-fuel car of LPG and gasoline essentially requires a vaporizer, a mixer, and LPG fuel bomber, a solenoid valve, and LPG engine control units for controlling the solenoid valve.
Due to the above essential constitution, the manufacturing cost of a dual-fuel car of LPG and gasoline has increased, and the manufacturing process thereof has been complicated.